(1) Field of the Invention
The present invention relates to an equipment for detecting the movement of a preceding vehicle and giving warning. More particularly, the invention relates to an equipment of a vehicle such as an automobile and a truck which equipment, when the vehicle is at a stop, detects the forward or backward movement of a preceding vehicle and gives warning to the driver of the vehicle. In the present specification and claims, "the vehicle" means a vehicle of one's own, and "preceding vehicle" means a vehicle existing in front of the vehicle.
(2) Description of the Prior Art
Vehicle equipments for detecting the distance between moving vehicles and giving warning to the driver are already known. When the vehicle is moving, these equipments detect the distance between the vehicle and a preceding vehicle or a succeeding vehicle and give warning to the driver of the vehicle if the measured distance becomes shorter than a predetermined value. However, the equipment for detecting the movement of a preceding vehicle and giving warning as described above has not been provided yet.
As long as the vehicle is on the road, it is needless to say that the driver must keep carefully looking to the front even when the vehicle is stopped because of a traffic signal or a traffic jam. In large cities and the suburbs thereof at present, vehicles are forced to stop very frequently because of traffic signals, traffic jams, etc. Such frequent stoppages make the driver tired.